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  Some people think quartz watches be just quartz watches. But beauty is in the eye of the beholder and to me a marine chronometer quartz watch is more, than just a "normal" quartz watch! It goes far beyond that. It is an instrument, which at times not long ago was beyond price. John Harrison was the first person that actually created a working marine chronometer. A marvel at its time. Modern high accuracy quartz watches link us with the time where navigation on the oceans was an art by itself and the used instruments were invaluable. That's how I describe my quartz watch!


What is a Marine Chronometer?

A Marine Chronometer is a watch with an accuracy high enough (what this means, you will see later) to determine the longitude of a position on land and more importantly on sea. To get a general overview of what a Marine Chronometer is you can check out Wikipedia:

Accuracy of a Marine Chronometer

There is not much written about the minimum requirements of a Marine Chronometer. As a rule of thumb we can say that a Marine Chronometer should not loose or win more than 2 seconds per month. Also important, accuracy must be granted under all sorts of different conditions as temperatures or shocks. With this rule we can state that a Marine Chronometer is within +/- 24 Seconds per year. To give you a comparison, a normal quartz watch is within +/-30 seconds/month and a good mechanical wristwatch on the other hand is within 90 seconds/month.

Reasonable Accuracy Expectations
by Type of Watch
Seconds gain/loss per day Best
Worst Typical Best
Vintage mechanical watch
in good repair
+/-60 +/-15 +/-5 99.9826%
Modern mechanical watch
+/-10 +/-5 +/-2 99.9942%
Modern mechanical watch
chronometer certified
+6/-4 +/-3 +/-1 99.9977%
Modern quartz watch
non-certified (normal)
+/-2 +/-1 +/-0.1 99.9998%
Modern quartz watch
marine chronometer quality
+/-0.02 +/-0.02 +/-0.0 99.9999%
Source: http://www.chronocentric.com/watches/accuracy.shtml